Shower Drainage

ABSTRACT

A pump for use with a shower base includes a pump chamber ( 12 ) having an inlet for receiving water from a shower base and an outlet ( 14 ) through which the water is pumped; such that the inlet can be connected to the shower base such that the water drains directly into the pump chamber ( 12 ) from the shower base. A wet floor former ( 55 ) for supporting a water resistant floor covering material, comprises a base having a predetermined fall, and a trap towards which the fall is directed, the trap comprising a sump which is provided on the base, a shower water inlet through which water from the floor covering material can enter the sump, and a waste water outlet, the sump acting as the pump chamber ( 12 ) when a pump is installed.

This invention relates to shower drainage. In particular it relates todrainage from showers that require pumping to drain water from theshower. The invention is also applicable to showers constructed usingwet floor formers.

In conventional showers, water drains under the effect of gravity. Thiscan occur because the base of the installation is formed from a traythat is typically mounted slightly above floor level and has a rimformed around its periphery to retain water while it drains from thebase through a drain hole.

There are certain cases in which it is difficult or impossible to locatethe shower tray sufficiently above the drain for gravity to cause waterto flow properly into the drain. Access to a conventional installationcan require a step up from floor level to enter the shower. Even thoughthis step might be relatively small, it can still represent a majorhindrance to people with physical disabilities, the old-aged orwheelchair bound, for whom the step up is either very difficult or, insome cases, impossible. In order to accommodate such people, it isdesirable to mount the shower tray as close to floor level as possible,possibly flush with floor level. However, when this is done, it can bedifficult to obtain sufficient vertical separation between the showertray and the drain to achieve effective gravity drainage. Similarproblems occur with wet floor bathrooms when the floor is gently slopedto a drain by grading the floor or by installing a Wet Floor Former. Insuch an installation, all or part of the floor of the room is coveredwith a waterproof covering and the floor under the covering slopes downto a drain. Such a floor is created by using a wet floor former: astructural former, typically made from glass reinforced plastic, metalor other such materials which defines the shape of the wet floor, inparticular the fall towards the drain hole, and over which thewaterproof covering is laid. Low level trays are also becoming popularfor general applications in the domestic market, irrespective of theability of the user.

One solution to the problem of difficult drainage by gravity is to fit apump to the waste outlet from the shower to pump waste water into thedrain at a rate sufficient to prevent the shower tray from filling withwater. Examples of pumped waste systems for showers can be found in GB1,532,953; GB 2,224,777; GB 2,276,541; GB 2,288116; GB 2,294,636; GB2,361,429 and GB 2,373,515.

GB 2,276,541 and GB 2,294,636 describe shower trays which have a recessinto which water flows. An electric pump is located above the showertray and sucks water from the recess by means of a pipe which projectsinto the recess from above. GB 1,532,953; GB 2,224,777; GB 2,288116; GB2,294,636; GB 2,361,429 and GB 2,373,515 describe shower trays with awaste outlet through which water drains into a sump (chamber or gullytrap), the water again being sucked therefrom through a pipe connectedto an electric pump.

GB 2,373,515 describes a floor drain for a shower which includes a wetfloor former for supporting a water resistant floor covering material,the former comprising a base having a predetermined fall, and a traptowards which the fall is directed, the trap comprising a sump which isprovided on the base, a shower water inlet through which water from thefloor covering material can enter the sump, a waste water outlet, a pumpfor causing at least a portion of the said water to flow from the sumpthrough the waste water outlet, and a clamp which surrounds the showerwater inlet and by which the floor covering material can be clamped tothe base. The pump is located incorporated into the waste water outlet(discharge pipe).

These systems suffer from a number of problems. A typical electricallyheated shower can deliver water at 6-8 litres/minute. In order that theshower should not fill up and flood the room in which it is located, thepump must remove water at a rate no less than this and so the pump istypically rated at around 10-12 litres/minute. Such pumps are large,making it difficult to locate the pump below the shower tray. They arealso noisy. As the pump draws at a rate greater than the water flowsfrom the shower, it will also draw a large amount of air through thedrainage system. This can lead to air locks forming in the system,preventing effective drainage, and causes more noise.

GB 2,224,777 proposes providing a sump below the shower tray andoperating the pump only when sufficient water has entered the sump toactivate an operating switch. In order to avoid the pump continuouslyswitching on and off, it is necessary that the sump is relatively largeand that there is a delay between the water level dropping low enough todeactivate the pump and the pump actually stopping. This makesinstallation difficult and can lead to oscillation when the shower isstopped as water draining back from the pump when it stops can besufficient to reactivate the pump. The water draining out of the pumpcan still cause air lock problems. It has been proposed to mount thepump in the sump itself. However, the large physical size of the pumpmeans that this can be difficult to install if there is limited verticalspace available below the shower tray. The pump is also vulnerable toblockage by hair or the like, a problem common to most existingpumped-outlet shower systems.

It is an object of this invention to provide a pumped-outlet showerwhich does not suffer from some or all of these problems.

It is another object of this invention to provide a wet floor former forcreating a shower installation that can be supplied with a pump toassist drainage which does not suffer from some or all of theseproblems.

This invention attempts to address these problems by positioning a pumpin the shower tray drain outlet or the wet floor former so that the traydrains directly into the pump chamber.

A pump according to the invention comprises a pump chamber having aninlet for receiving water from the shower base and an outlet throughwhich the water is pumped; characterised in that the inlet can beconnected to the shower base such that the water drains directly intothe pump chamber from the shower base.

The pump can have a motor mounted above or below the pump chamber. Therecan also be a filter cover mounted above the pump chamber to preventblockage of the chamber. Where the motor is located above the pumpchamber, it can be positioned so as to be entirely below the cover.

By positioning the pump chamber to receive water from the showerdirectly, the problems associated with the need to suck water from asump are avoided. Thus the pump can be of lower power and problems ofair locks are reduced. The preferred form of pump is a Centrifugal pump,although other forms of pump can also be used with the same benefits.The motor is mounted above the chamber, and drives the impeller by meansof a drive shaft which passes through the shower drain outlet.

This pump can be used in a shower tray arrangement, with the pumpchamber being optionally formed integrally with the shower tray, or in awet-floor former in which a waterproof upper layer on the former isclamped to the pump.

The invention also comprises a wet floor former for supporting a waterresistant floor covering material, the former comprising a base having apredetermined fall, and a trap towards which the fall is directed, thetrap comprising a sump which is provided on the base, a shower waterinlet through which water from the floor covering material can enter thesump, and a waste water outlet, the sump being configured as a pumpchamber for receiving a pump mechanism for pumping water from the sumpthrough the waste water outlet.

By configuring the sump as a pump chamber, it is possible to fit a pumpafter the former has been installed without the need to have accessbelow the base. Also, because such a sump can operates without a pumpmechanism, either for a gravity drain, or when attached to another pumpsystem in the discharge, it is only necessary to have one type of formerfor any installation.

The sump is preferably formed integrally with the base, although it canalso be formed separately and attached prior to installation.

It is also preferred that a clamp is provided which surrounds the showerwater inlet and by which the floor covering material can be clamped tothe base, typically attaching directly to the sump/pump chamber.

The invention will now be described by way of examples, with referenceto the accompanying drawings, in which:

FIG. 1 shows a pump according to one embodiment of the invention;

FIG. 2 shows an exploded view of the pump of FIG. 1;

FIG. 3 shows an underneath view of the pump of FIG. 1;

FIG. 4 shows the pump of FIG. 1 installed in a shower tray;

FIG. 5 shows a separated view of the pump, cover and shower tray of FIG.4.

FIG. 6 shows a shower installation with a wet floor former according toone embodiment of the invention; and

FIG. 7 shows a detailed view of the sump of FIG. 6.

Referring now to the drawings, a pump according to one embodiment of theinvention is shown in FIG. 1, in exploded and part-cutaway view. Thepump comprises a sump body 10 formed from a moulded plastic material andhaving an open-topped, shaped pump chamber 12 and an outlet 14 definedtherein. The sump body 10 is formed with a flange 16 allowing it to besecured in a shower drain hole as will be descried below. A top plate 17is fixed over the pump chamber 12. The top plate 17 has a hole 19 formedin a central region thereof. A motor housing 18 is provided for fixingon top of the top plate 17 and above the base of the shower (not shown)and enclosing an electric motor 20 (together with an associatedelectrical controller 21) which drives an impeller 22 located in thepump chamber 12 by means of a drive shaft 24 passing from the motor 20through the hole 19. A cover 26 sits over the housing 18. The cover 26is provided with apertures 27 for allowing water to drain through intothe pump through the hole 19 but to catch and filter out items such ashair which might otherwise block the pump or drain.

A non-return valve 28 is positioned in the outlet 14 to prevent waterflowing back into the pump chamber 12 when the pump is not active. Inthe present case, the valve 28 is in the form of a flap which is formedintegrally with a resilient gasket 30 positioned between the sump body10 and top plate 17.

The motor 20 is a low voltage electrical motor and is connected to apower supply in the normal manner (not shown). Sensors (not shown) arealso provided in the pump chamber 12 for detecting the presence ofwater. These sensors can be used to automatically activate the pump whensufficient water has flowed from the shower to cover the impeller 22,and to stop the pump when the water falls below this level for anyreason. The sensors can be of a number of different forms, for example asensor probe extending down into the pump chamber 12 to a predeterminedheight above the base thereof, or spaced electrodes in the pump chamber.

In use, the sump body 10 sits in the drain hole 31 of a shower tray 32and secured thereto by means of three fixing lugs in mounting blocks 33from below (screws or any other suitable form of fastening, or a ringnut may also be used). A gasket 34 can be provided to seal the join andprevent water leakage around the outside of the pump. The top plate 16,housing 18, motor 20 and impeller 22, and the cover 26 are connected asdescribed above. The outlet 14 of the pump is connected to a waste pipe36. It is particularly preferred that this pipe 36 be flexible in orderto accommodate obstructions in the drainage path. The pipe 36 connectsto a drain in the normal manner.

In an alternative construction, the sump body 10 is formed integrallyWith the shower tray 32, the remaining parts being connected as above.

A further embodiment of the invention has the motor mounted below thesump body 10 driving upwardly though the base thereof into the chamber12. Such an arrangement is dependent on sufficient space being availableto house the pump. This is not usually the case with normal electricmotors. However, new designs of motor are becoming available which haverelatively low profiles which may allow such an arrangement to be used.Even with this arrangement, the characteristic of the invention remains,namely that the shower drains directly into the pump chamber, with allof the benefits discussed previously.

A shower installation including a wet floor former according to oneembodiment of the invention is shown in FIGS. 6 and 7 and is formed in acorner of a room with the two adjoining walls 51, 52 being tiled and theshower head 53 being attached to the wall 51 in the normal manner. Thebase 54 is provided in the form of a wet floor former 55 with awaterproof covering 56 secured to its upper surface. A drain 57 isformed part way along one edge and close to the wall 52. The waterproofcovering 56 is secured to the former 55 around the drain opening bymeans of a clamping ring 61 that is positioned on top of the coveringand screwed into the base 55. The regions 58 of the base 54 around thedrain 57 are sloped such that water naturally flows towards the drain57. A sump 59 is formed integrally with the base 54 in the drain 57. Apump attaches to the sump in the manner described below.

A pump suitable for installation in a wet floor former as shown in FIGS.6 and 7 can be as is described in relation to FIGS. 1-3 above.

The wet floor former 55 of the invention is installed by eitherproviding a wet concrete layer into which the former is pushed, theconcrete then being allowed to set; or by being fixed directly on top oftimber floor joists. The waterproof covering 56 can then be secured inthe normal manner. The outlet from the sump is connected to a wastewater pipe in the normal manner. If the waste pipe is capable ofdraining under gravity, or alternatively already includes a pump, allthat is required is to fit a cover to stop hair or other material fromentering the sump and blocking the outlet. If no pump is fitted, and itbecomes evident that one is required, either on original installation orthereafter, it is a relatively easy job to fit the pump mechanism intothe sump to improve drainage.

Further changes can be made while staying within the scope of theinvention.

1. A pump for use with a shower base, comprising a pump chamber havingan inlet for receiving water from the shower base and an outlet throughwhich the water is pumped; characterised in that the inlet can beconnected to the shower base such that the water drains directly intothe pump chamber from the shower base.
 2. A pump as claimed in claim 1,further comprising a filter cover mounted over the pump inlet.
 3. A pumpas claimed in claim 2, further comprising a motor mounted above the pumpchamber and below the filter cover.
 4. A pump as claimed in claim 3,wherein the motor is located above the level of the shower base.
 5. Apump as claimed in claim 4, wherein the motor drives an impellerpositioned in the pump chamber by means of a drive shaft which passesthorough a waste opening in the shower base through which water alsodrains into the pump chamber.
 6. A pump as claimed in claim 1, furthercomprising a motor mounted below the pump chamber.
 7. A pump as claimedin claim 1, further comprising sensors for detecting the presence ofwater in the pump, output from the sensors being used to operate thepump.
 8. A pump as claimed in claim 1, comprising a non-return valve inthe pump chamber.
 9. A shower base unit having a drain opening andcomprising the pump of claim 1 connected directly to the drain opening.10. A shower base unit as claimed in claim 9, wherein a filter cover ismounted over the drain opening, the pump being located below the draincover.
 11. A shower base unit as claimed in claim 9, comprising a tray.12. A shower base unit as claimed in claim 11, wherein the pump chamberis formed integrally with the tray.
 13. A shower base unit as claimed inclaim 9 comprising a former having an upper waterproof layer which isclamped around the pump inlet.
 14. A wet floor former for supporting awater resistant floor covering material, the former comprising a basehaving a predetermined fall, and a trap towards which the fall isdirected, the trap comprising a sump which is provided on the base, ashower water inlet through which water from the floor covering materialcan enter the sump, and a waste water outlet, the sump being configuredas a pump chamber for receiving a pump mechanism for pumping water fromthe sump through the waste water outlet.
 15. A wet floor former asclaimed in claim 14, wherein the sump is formed integrally with thebase.
 16. A wet floor former as claimed in claim 14, further comprisinga clamp surrounding the shower water inlet and by which the floorcovering material can be clamped to the base.
 17. A wet floor former asclaimed in claim 16, wherein the clamp attaches directly to the sump.18. A shower base comprising a wet floor former as claimed in any ofclaims claim 14 and including a waterproof covering secured to the base.19. A shower base as claimed in claim 18, further comprising a pumpmechanism mounted in the sump.
 20. A shower base comprising a wet floorformer for supporting a water resistant floor covering material, theformer comprising a base having a predetermined fall, and a trap towardswhich the fall is directed, the trap comprising a sump which is providedon the base, a shower water inlet through which water from the floorcovering material can enter the sump, and a waste water outlet, the sumpbeing configured as a pump chamber for receiving a pump mechanism forpumping water from the sump through the waste water outlet, wherein saidshower base includes a covering secured to the base and the pumpmechanism is mounted in the sump as claimed in claim 19, wherein thepump mechanism is a pump as claimed in claim 1.